Pask, who joined the Saints' board as a non-executive director in January 2007, has been given a new contract by the RFU as England Senior Team Physiotherapist.
Pask's connection with the Saints stretches over 26 years and includes 150 first team appearances as a player and eight years as a fitness trainer and then physiotherapist, including at the 2000 Heineken Cup final.
Saints chairman Leon Barwell thanked Pask for his service to the club, and said that while the formal association may be ending he was sure that Pask would continue to be a familiar face in the stands at Franklin's Gardens.
"Phil has been something of a Saints institution for more years than we care to remember, first as a player, then in the backroom staff and latterly as a non-executive director," he said. "As a player he was wholeheartedly committed to the Saints' cause and played an important role in helping re-establish the team as a force in English rugby. Then as a fitness trainer and physiotherapist he played a crucial role working in taking us to Heineken Cup glory.
"Over the past few years the input, expertise and experience he has provided on the board of directors has been invaluable in helping us provide support to the playing department in particular and the club as a whole.
"I'm sure that Phil will continue to be a familiar face at Franklin's Gardens and he knows that he will always be welcome here at the Saints. On behalf of everyone at the club I'd like to thank Phil for his commitment and dedication over the years and we wish him all the best for the future."
Pask said that he will miss being formally involved at Franklin's Gardens.
"The Saints has been a part of my life for many years and I've thoroughly enjoyed being involved at every level of the club," he said. "I've worked with many great people, especially the Barwells, and am proud to have played a part in making the Saints such a great club.
"With Leon Barwell and Tony Hewitt leading the board, Allan Robson as chief executive and Jim Mallinder as director of rugby I know that the future is bright both on and off the field, and I'm certainly going to enjoy watching it all happen."